JP5142734B2 - Control device and control method for pressurized fluidized bed boiler - Google Patents

Description

  The present invention relates to a control apparatus and a control method for a pressurized fluidized bed boiler that controls combustion of the pressurized fluidized bed boiler.

  The pressurized fluidized bed boiler has higher combustion efficiency and can make the equipment more compact than an atmospheric boiler that burns fuel at atmospheric pressure. In a pressurized fluidized bed boiler, a pulverized coal is mixed with water and limestone to form a slurry, that is, CWP (Coal Water Paste). By using such CWP as fuel, the pressurized fluidized bed boiler generates high-temperature and high-pressure steam and gas, operates a steam turbine generator or a gas turbine generator, and enables combined power generation.

On the other hand, various controls are performed on the pressurized fluidized bed boiler side in order to respond to the output requested by the generator side (see, for example, Patent Document 1). For example, the output of the steam turbine generator is set in the output setter (ALR), and the command value based on the set output is converted into the output instruction (MWD) of the steam turbine generator. Thereafter, the actual output of the steam turbine is compared with the output instruction (MWD), and a boiler input command (BID) of the pressurized fluidized bed boiler is issued based on the comparison result. That is, the amount of CWP to be supplied is controlled on the pressurized fluidized bed boiler side with respect to the required output of the steam turbine generator. Specifically, if the output of the steam turbine generator is insufficient, control is performed to increase the amount of CWP, and vice versa.
JP-A-10-73207

By the way, the heat source of the pressurized fluidized bed boiler is CWP coal. For example, if L / C is high, the amount of limestone in CWP increases, and the amount of coal decreases compared to the case where L / C is low. become. L / C represents the ratio of dry coal (C), which is dry coal, and limestone (L) by the following formula.
L / C = Limestone ratio / Coal ratio If the amount of coal in CWP is small and a boiler input command (BID) indicating an increase in output is issued, as shown in FIG. The amount of air is increased in advance by the boiler acceleration command (BIR), and then the amount of fuel, which is the amount of CWP, is increased to reach the amount of CWP L1 (broken line portion) according to the boiler input command (BID). To do.

  Between time T1 and T2, the amount L1 of CWP commensurate with the boiler input command (BID) was reached. However, since the amount of coal in the CWP is small, the actual output of the steam turbine generator and the steam turbine generator And a control for increasing the amount of CWP is performed. In the meantime, the air amount has reached an amount commensurate with the amount of CWP. However, the air amount actually becomes excessive, and the air amount is temporarily reduced by O2 control, and thereafter the control is performed so as to become the O2 set value. Done.

  Between time T2 and T3, the amount of CWP increases and the output of the steam turbine generator reaches the output instruction (MWD), and the amount of air commensurate with the combustion of CWP and the air supplied to the pressurized fluidized bed boiler There is no difference in the amount, and the amount of CWP is stabilized. When the amount of CWP is stabilized, the amount of air becomes stable and constant because the O2 concentration is stabilized.

  Thus, when the amount of coal in CWP is small, fluctuations in the air amount occur between the times T1 and T2 and the first part of the times T2 to T3. That is, if the amount of coal in the CWP does not correspond to the fuel amount of the output instruction, the air amount does not match the fuel amount when the output fluctuates, so the operation of the pressurized fluidized bed boiler becomes unstable. As a result, the air becomes excessive in the pressurized fluidized bed boiler, causing ash scattering to the empty part of the pressurized fluidized bed boiler and NOx increase, and the heat transfer tubes provided in the boiler are worn. May progress.

  On the other hand, the following problems occur in a power generation unit having a plurality of pressurized fluidized bed boilers. As shown in FIG. 11, the unit may be provided with two pressurized fluidized bed boilers (A furnace, B furnace). In FIG. 11, a generator and the like are omitted. In the case of a unit including a plurality of pressurized fluidized bed boilers, the load distribution of each boiler may be different. For example, the A furnace performs heat exchange with the main steam, and the B furnace corresponds to a time when heat exchange is performed with the main steam and reheat steam. Thus, if the load distribution with respect to a pressurized fluidized bed boiler differs, the combustion characteristic of each boiler will differ. In this case, in order to prevent unnecessary consumption of limestone and to reduce the amount of BM generated in the boiler, the A furnace produces CWP in the A fuel production system, and the pump P is driven by the fuel supply command to Supply. On the other hand, in the B furnace, CWP is manufactured by the B fuel manufacturing system, and the pump P is driven by the fuel supply command to supply CWP. In other words, CWPs with different amounts of coal and limestone are produced for each pressurized fluidized bed boiler and supplied to each boiler.

  In a unit including a plurality of pressurized fluidized bed boilers, the total fuel amount (TFRD) is distributed to the A furnace and the B furnace as shown in the “normal state” of FIG. For this reason, the ratio of the amount of CWP supplied to each pressurized fluidized bed boiler is constant. In FIG. 12, the steam turbine generator is described as ST generator, and CWP is described as fuel. Here, if the amount of coal of CWP supplied to the A furnace, that is, the amount of heat, is small, as shown by “A furnace load reduction” in FIG. 12, the boiler load of the A furnace is insufficient, and the output instruction (MWD) A difference occurs in the output of the steam turbine generator. As a result, as shown by “control operation” in FIG. 12, control for increasing the total fuel amount (TFRD) is performed. Then, in order to distribute the total fuel amount to the A fuel production system and the B fuel production system, the amount of CWP in the A furnace and the B furnace increases.

  As a result, compared with the load ratio of the A and B furnaces shown in the “normal state” of FIG. 12, the load ratio of the A and B furnaces shown in the “control operation” of FIG. To do. That is, there is a difference in load distribution between the A furnace and the B furnace. The load of the pressurized fluidized bed boiler which is a B furnace adjusts the heat exchange amount by increasing the fluidized bed height or fluidized bed temperature in the boiler. In a pressurized fluidized bed boiler, if the fluidized bed is raised to an empty tower without a heat transfer tube, the amount of ash scattering increases and trouble on the wake side tends to occur. On the other hand, in order to suppress the fluidized bed temperature below the flow inhibition prevention temperature of the BM in the boiler, an upper limit is provided for the fluidized bed temperature.

  Therefore, in the B furnace in which the load ratio collapses and the load becomes large, the fluidized bed height or fluidized bed temperature approaches the upper limit value, and it is necessary to suppress the output of the unit.

  The purpose of the present invention is to solve the above-mentioned problems, keep the pressurized fluidized bed boiler stable, and, when there are a plurality of pressurized fluidized bed boilers, pressurization that can prevent the load ratio of the boiler from collapsing. It is providing the control apparatus and control method of a fluidized bed boiler.

According to the first aspect of the present invention, a CWP produced by a fuel production system capable of controlling a composition ratio of a plurality of coals, limestones and water is respectively applied to pressurized fluidized bed boilers having a plurality of different load distributions via a plurality of supply systems. When supplying, the CWP total fuel amount is determined on the basis of the command value for setting the output of the generator that generates power with steam from each boiler and the output of the generator, and the total fuel amount is supplied to the boiler. In the control method of the pressurized fluidized bed boiler to be distributed, supply to the boiler based on the amount of CWP coal supplied to the pressurized fluidized bed boiler and the amount of coal set for the boiler The amount of CWP to be calculated is calculated, the ratio of the calculated coal amount of each CWP is compared with the ratio of the set coal amount, and the amount of water injection is adjusted for the CWP supplied to each boiler. of Inform whether a PFBC control method for a boiler, characterized in that.

The invention of claim 2 is the control method of the pressurized fluidized bed boiler according to claim 1 , wherein the amount of CWP coal supplied to the pressurized fluidized bed boiler and the coal set for the boiler A corresponding amount of CWP corresponding to the difference from the amount is determined, the corresponding amount is added to the amount of the total fuel amount allocated, and the CWP is supplied to the pressurized fluidized bed boiler, respectively.

The invention of claim 3 is the method of controlling a pressurized fluidized bed boiler according to claim 1 or 2 , wherein the ratio of coal is calculated based on the ratio of dry coal and limestone and the ratio of moisture of CWP, The amount of coal is calculated from the amount of CWP supplied to the pressurized fluidized bed boiler and the coal ratio.

A fourth aspect of the present invention, each of a plurality of coal and limestone water multiple load distribution are different PFBC boiler CWP produced by the composition ratio can be controlled fuel production system through a plurality of supply system When supplying, the CWP total fuel amount is determined on the basis of the command value for setting the output of the generator that generates power with steam from each boiler and the output of the generator, and the total fuel amount is supplied to the boiler. In the control device for the pressurized fluidized bed boiler to be distributed, supply to the boiler based on the amount of CWP coal supplied to the pressurized fluidized bed boiler and the amount of coal set for the boiler The amount of CWP to be calculated is calculated, the ratio of the calculated coal amount of each CWP is compared with the ratio of the set coal amount, and the amount of water injection is adjusted for the CWP supplied to each boiler. of Control means for informing whether, as the control device for the PFBC boiler, characterized in that it comprises a.

According to the first and fourth aspects of the invention, the amount of CWP supplied to the boiler is determined based on the amount of coal in the CWP and the amount of coal set for the pressurized fluidized bed boiler. The amount of CWP corresponding to the output of the steam turbine generator, that is, the boiler load can be supplied to the boiler. As a result, the operation of the pressurized fluidized bed boiler can be stabilized.

Moreover , even if there are a plurality of pressurized fluidized bed boilers, the amount of CWP supplied to the boiler is determined based on the actual amount of CWP coal and the amount of coal set for the pressurized fluidized bed boiler. Since it determines, CWP can be supplied to a boiler according to each boiler load. As a result, collapse of the load ratio of the pressurized fluidized bed boiler can be prevented.

According to the invention of claim 2 , the amount of CWP supplied to the pressurized fluidized bed boiler based on the difference between the amount of coal in the CWP and the amount of coal set for the pressurized fluidized bed boiler. Therefore, the amount of CWP can be obtained by simple arithmetic processing.

According to invention of Claim 3 , a coal ratio is calculated using the ratio (L / C mentioned later) of dry coal and limestone, and the ratio of the moisture of CWP, and the amount of coal is calculated using this coal ratio. Therefore, the amount of CWP supplied to the pressurized fluidized bed boiler can be calculated by a simple arithmetic process using two values.

  Next, embodiments of the present invention will be described in detail with reference to the drawings.

(Embodiment 1)
The control device for the pressurized fluidized bed boiler according to this embodiment is the control device 18 shown in FIG. The unit including the control device 18 includes fuel production systems 11 and 12, supply systems 13 and 14, an A furnace 15, a B furnace 16, and a power generator 17.

  The fuel production system 11 produces fuel to be supplied to the A furnace 15, and produces CWP from pulverized coal, limestone, and water. At this time, the fuel production system 11 adjusts the constituent ratio of coal, limestone, and water under the control of the control device 18. Similarly, the fuel production system 12 produces CWP to be supplied to the B furnace 16, and adjusts the composition ratio of coal, limestone, and water of the CWP by the control of the control device 18.

  The supply system 13 sends the CWP produced by the fuel production system 11 to the A furnace 15 under the control of the control device 18. The supply system 13 includes a plurality of pumps (P). In this embodiment, the supply system 13 includes a pump (A1P) 13A and a pump (A2P) 13B. Similarly, the supply system 14 sends CWP produced by the fuel production system 12 to the B furnace 16 under the control of the control device 18, and includes a pump (B1P) 14A and a pump (B2P) 14B. .

  A furnace 15 and B furnace 16 are pressurized fluidized bed boilers that burn CWP and generate high-temperature and high-pressure steam, respectively. As shown in FIG. 2, the A furnace 15 and the B furnace 16 are provided with a pressure vessel 15A and a pressure vessel 16A. The pressure vessel 15A and the pressure vessel 16A combust CWP with compressed air to generate a fluidized bed FA and a fluidized bed FB. Since the heat transfer tube 15B is provided in the pressure vessel 15A and the pressure vessel 16A and water is supplied to the heat transfer tube 15B, the heat transfer tube 15B generates high-temperature and high-pressure steam. This steam is supplied to the power generator 17 as main steam. Further, the steam once worked in the power generation device 17 is supplied to the heat transfer tube 16B provided in the pressure vessel 16A, and the heat transfer tube 16B generates high-temperature steam. This steam is supplied to the power generator 17 as reheated steam. The A furnace 15 and the B furnace 16 are provided with a BM tank 15C and a BM tank 16C for taking in and out the pressure medium 15A and the fluid medium (BM) in the pressure container 16A.

  In this way, the A furnace 15 exchanges heat with the main steam, and the B furnace 16 exchanges heat with the main steam and reheated steam. Therefore, the load distribution differs between the A furnace 15 and the B furnace 16.

  The power generator 17 drives a steam turbine generator (not shown) with high-temperature and high-pressure main steam and reheat steam generated by the A furnace 15 and the B furnace 16. Although not shown, the power generator 17 also drives a gas turbine generator (not shown) with high-temperature and high-pressure combustion gas generated by the combustion of CWP.

  The control device 18 is a computer that controls the fuel production systems 11 and 12 and the supply systems 13 and 14. The control device 18 controls the production of CWP by the fuel production systems 11 and 12. For example, as shown in FIG. 3, CWP is manufactured by pouring and mixing water with adjusted water amount into coarsely pulverized coal, slurry, and limestone with adjusted limestone amount. Coarse pulverized coal is adjusted by the amount of dry coal and the amount of water. Slurry is made from finely pulverized coal and water with adjusted water content, and finely pulverized coal is adjusted by dry coal amount and water amount.

  The CWP coal burns in the A furnace 15 and the B furnace 16 to heat the heat transfer tubes 15B and the heat transfer tubes 16B. Since the heat transfer tube 15B and the heat transfer tube 16B are supplied with water, the coal serves as a heat source for generating steam. The limestone of CWP desulfurizes in the A furnace 15 and the B furnace 16 to suppress SOx. At the same time, the limestone is used to maintain the fluidized bed height in A furnace 15 and B furnace 16. That is, by adjusting the fluidized bed height, the heat transfer area between the heat transfer tube 15B and the fluidized bed FA in the pressure vessel 15A, the heat transfer between the heat transfer tube 15B and the heat transfer tube 16B and the fluidized bed FB in the pressure vessel 16A. The load adjustment of the A furnace 15 and the B furnace 16 is performed by increasing / decreasing the area. CWP water adjusts the viscosity of CWP. The boiler efficiency of the A furnace 15 and the B furnace 16 is higher as the amount of CWP water is smaller, and the viscosity is preferably closer to the upper limit value. However, if the viscosity of CWP exceeds the upper limit value, it will lead to blockage in the piping and overload of the fuel pump. Moreover, if the viscosity of CWP falls below the lower limit, not only will the boiler efficiency decrease, but the coal coarse particles and water in the CWP will easily separate, and the coal coarse particles will settle and block in the piping. There is a possibility of waking up. Furthermore, even if the viscosity is within the adjustment range, depending on the coal type, it is likely to be clogged, and the amount of water in the fuel is not constant. Therefore, in this embodiment, the viscosity of CWP is set to a predetermined range set in advance.

The control device 18 adjusts the fluidized bed height generated inside the A furnace 15 and the B furnace 16 by L / C representing the ratio of dry coal (C) and limestone (L), which are dry coal, and generates a power generator. 17 outputs are controlled. The control device 18 calculates L / C based on the coal ratio and the limestone ratio,
L / C = Limestone ratio / Coal ratio (1)
Calculated by For example, as shown in FIG. 4, when dry coal is 68.2 [%], limestone is 6.82 [%], and water is 25 [%]
L / C = 6.82 / 68.2 [%] = 10 [%]
It becomes. In this embodiment, the CWP configuration ratio in FIG. 4 is used as a standard. The coal ratio of formula (1) is the ratio of coal to CWP, and the limestone ratio is the ratio of limestone to CWP. L / C is a value input from the input screen of the control device 18, and is an arbitrarily set value.

  The control device 18 sends an A1P pump command and an A2P pump command for controlling the pump (A1P) 13A and the pump (A2P) 13B of the supply system 13 to the supply system 13, and the pump (B1P) 14A and the pump of the supply system 14 (B2P) A B1P pump command and a B2P pump command for controlling 14B are sent to the supply system 14. For this purpose, as shown in FIG. 5, the control device 18 performs processing including a unit master 18A, a boiler master 18B, a water-fuel ratio master 18C, a fuel master 18D, and a pump control unit 18E.

  The unit master 18A converts the automatic load control (ALR) setting set in the output setting device (not shown) into an output command (MWD) by function generation (FG), and this output command (MWD) is converted into the boiler master 18B. To pass.

  The boiler master 18B performs subtraction between the ST generator output, which is a value actually output by the power generation device 17, and the output command (MWD), and further adds the subtraction result to the output command (MWD) to generate a boiler input command (BID). ) Is calculated. For example, when the actual ST generator output is lower than the output command (MWD), the load of the pressurized fluidized bed boiler is increased by the boiler input command (BID). The boiler master 18B passes the calculated boiler input command (BID) to the water-fuel ratio master 18C.

  The water-fuel ratio master 18C calculates the fuel amount corresponding to the boiler input command (BID) by function generation (FG), and calculates the calculated fuel amount by the steam temperature supplied to the power generator 17 by division with correction (DV). The total fuel amount (TFRD) is calculated after correction. That is, the water-fuel ratio master 18C corrects the calories of the coal used by division with correction (DV). Then, the water-fuel ratio master 18C passes the calculated total fuel amount (TFRD) to the fuel master 18D.

The fuel master 18D calculates the fuel amount (FRD) of the A furnace 15 and the fuel amount (FRD) of the B furnace 16 from the total fuel amount (TFRD) by function generation (FG). In FIG. 5, the fuel amount (FRD) of the A furnace 15 and the fuel amount (FRD) of the B furnace 16 are represented as “◯ furnace FRD”. Further, in this embodiment, the fuel amount (FRD) of the A furnace 15 and the fuel amount (FRD) of the B furnace 16 are approximately equal to each other and are approximately half of the total fuel amount (TFRD). The fuel master 18D, when L / C is changed, the amount of fuel calculated (FRD) is corrected by the correction unit 18D _1.

The correction unit 18D ₁ corrects the fuel amount (FRD) for the A furnace 15 as follows. As shown in FIG. 6, the correction unit 18D ₁ is coal ratio of the target is set. This setting is the coal ratio setting. For example, 68.2 [%] in FIG. 4 is set as the coal ratio, and this value is set. The correction unit 18D _1, the current dry coal weight coal ratio current value. The control device 18 calculates the present coal ratio current value as follows. First, a part of the manufactured CWP is collected as a sample, and moisture measurement is performed. That is, the moisture content in the CWP (hereinafter referred to as “CWP moisture”) is measured by evaporating moisture from the total weight of the sample and removing the weight of the remaining sample from the total weight. Also,
Coal ratio + limestone ratio = 1-CWP moisture (2)
There is a relationship. On the other hand, as I mentioned earlier,
L / C = Limestone ratio / Coal ratio (1)
Therefore, from Equation (1) and Equation (2),
Coal ratio = (1-CWP moisture) / (1 + L / C) (3)
The relationship is obtained.

When the coal ratio setting is performed, the correction unit 18D ₁ uses the coal ratio set in the coal ratio setting to set the target dry coal amount for the A furnace 15 (hereinafter referred to as “dry coal amount target”). calculate. When the current value of the coal ratio is input, the correction unit 18D ₁ inputs the amount of dry coal included in the current CWP for the A furnace 15 (hereinafter referred to as “dry coal amount”) to the A furnace 15. It is calculated using the amount of CWP (hereinafter referred to as “A-CWP input amount”) and the coal ratio calculated by equation (3). The A-CWP input amount is a value input to the control device 18.

Then, the correction unit 18D ₁ is the difference between the dry coal weight goals and dry coal amount calculated by the subtraction (SUB), and calculates the amount of CWP corresponding to the calculated difference function generator (FG). When the corresponding amount of CWP is calculated, the correction unit 18D ₁ adds the corresponding amount of CWP to the fuel amount (FRD) of the A furnace 15 calculated by the fuel master 18D by addition (ADD), and adds the new amount of the A furnace 15 Fuel amount (FRD).

  Similarly, the fuel master 18D calculates a new fuel amount (FRD) of the B furnace 16.

  The pump control unit 18E uses an A1P pump command for controlling the pump (A1P) 13A of the supply system 13 and an A2P pump for controlling the pump (A2P) 13B based on the fuel amount (FRD) of the A furnace 15 calculated by the fuel master 18D. Commands are generated by function generation (FG), and these commands are sent to the supply system 13. By these pump commands, the fuel amount (FRD) calculated by the fuel master 18D is supplied to the A furnace 15. In FIG. 5, the A1P pump command and the A2P pump command are represented as “◯◯ CWP pump command”.

  Similarly, the pump control unit 18E controls the B1P pump command for controlling the pump (B1P) 14A of the supply system 14 based on the fuel amount (FRD) of the B furnace 16 calculated by the fuel master 18D, and the pump of the supply system 14 (B2P) B2P pump commands for controlling 14B are generated, and these commands are sent to the supply system 14.

  Next, a control method of the pressurized fluidized bed boiler using the pressurized fluidized bed boiler control device of this embodiment will be described. When the coal ratio of CWP changes, for example, when the bed height of the fluidized bed FA of the A furnace 15 decreases, the setting of L / C may be changed to maintain the bed height.

At such time, the control device 18 displays an input screen as shown in FIG. 7, for example. The input column 18 of the _input screen, the amount of CWP to be inputted to the A furnace 15 is inputted as "A-CWP-on amount", the amount of CWP to be inputted to the B furnace 16 is "B-CWP input amount" Is entered as Further, the input field ₁₈₂ of the input screen, the value of L / C is set for A furnace 15 is inputted as "A-L / C Setting", is set for B furnace 16 L / The value of C is input as “B / L / C setting”. Further, the input field 18 ₃ of the input screen, the proportion of water in the CWP to be inputted to the A furnace 15 is inputted as "A-CWP water", the proportion of moisture in the CWP to be inputted to the B furnace 16 Input as “B-CWP moisture”. In the case of measuring the rate of water automatically, input values for the input column 18 ₃ is not necessary.

Further, when displaying the determination result for the input to the input screen data, and operates the "determination result display" button 18 _11, to erase the entered data, the "data erasure" button 18 ₁₂ Manipulate.

When each data is input to the input screen, the control device 18 calculates the coal ratio using the fuel master 18D using the equation (3). In FIG.
Value of “AL / C setting” ... 10.5 [%]
Value of “BL / C setting” ... 10.0 [%]
And
Value of “A-CWP moisture” 25.2 [%]
Value of “B-CWP moisture” 23.5 [%]
So
Coal amount in A furnace 15 = CWP input amount x Coal ratio
= CWP input amount × {(1-CWP moisture) / (1 + L / C)}
= 48.8 × {(1-0.252) / (1 + 0.105)}
= 33.0
Is calculated by the control device 18. In the same way, the control device 18
Coal amount in B furnace 16 = CWP input amount x Coal ratio
= CWP input amount × {(1-CWP moisture) / (1 + L / C)}
= 51.6 × {(1−0.235) / (1 + 0.100)}
= 35.9
Is calculated. Thus, the control device 18, the display section 18 ₂₁ of the "dry coal weight calculation result" of the input screen, a dry coal content in the CWP to be inputted to the A furnace 15 to "A- dry coal amount" 33.0 [t / h] is displayed, and “B-dry coal amount” that is the amount of dry coal in the CWP charged into the B furnace 16 is displayed as 35.9 [t / h]. On the other hand, in the fuel master 18D of the control device 18, the “A-dry coal amount target” is 32.8 [t / h], for example, and the “B-dry coal amount target” is 36.1 [t / h], for example. It is. "A- dry coal amount target" and "B- dry coal amount target" is the dry coal amount target calculated using coal ratio set by the coal rate setting of the correction unit 18D _1.

Incidentally, "A- bias amount" in the display column 18 ₂₁ is as follows. Due to the characteristics of the A furnace 15 and the B furnace 16, the fuel amount of the B furnace 16 is controlled to exceed that of the A furnace 15 during operation at a high load. Moreover, the fluidized bed height and the bed temperature of the A furnace 15 are operated in the vicinity of the upper limit values, and the B furnace 16 tends to have a room for the fluidized bed height and the bed temperature. For this reason, in the A furnace 15, a value initially set as the target amount of dry coal, which is “1%” in FIG. 7, is added as a bias.

When these data are displayed, when the "judgment result display" button 18 ₁₁ is operated, the control unit 18 displays the determination result as shown in FIG. Thereby, if the determination result is the content that informs the adjustment of the value, the water injection amount of CWP and the like are adjusted.

Controller 18, and the data in the display column _{18 21} of the "dry coal weight calculation result" using the correction unit 18D _1, an "A- dry coal weight" 33.0 [t / h], "A- Subtraction with 32.8 [t / h] which is the “dry coal amount target” is performed, and the amount of CWP corresponding to 0.2 [t / h] which is the subtraction result is calculated. Thereafter, the control device 18, the correction unit 18D _1, A furnace fuel quantity of A furnace 15 was calculated by the fuel master 18D to (FRD), by adding corresponding amounts of CWP, fuel quantity A furnace 15 (FRD) And

  The control device 18 performs the same calculation process for the B furnace 16 and calculates the fuel amount (FRD) of the B furnace 16.

  Thereafter, the control device 18 issues an A1P pump command for controlling the pump (A1P) 13A of the supply system 13 and an A2P pump command for controlling the pump (A2P) 13B based on the calculated fuel amount (FRD) of the A furnace 15. Generate these and send these commands to the supply system 13. Based on these commands, the supply system 13 controls the pump (A1P) 13A and the pump (A2P) 13B, and supplies the calculated CWP of the fuel amount (FRD) of the A furnace 15.

  Similarly, the control device 18 generates a B1P pump command for controlling the pump (B1P) 14A of the supply system 14 and a B2P pump command for controlling the pump (B2P) 14B, and sends these commands to the supply system 14 Send to. The supply system 14 controls the pump (A1P) 14A and the pump (A2P) 14B based on these commands, and supplies the calculated CWP of the fuel amount (FRD) of the B furnace 16.

Thus, according to this embodiment, the A1P pump command and the A2P pump command and the B1P pump command and the B2P pump command are generated for the A furnace 15 and the B furnace 16 based on the amount of dry coal in the CWP. Therefore, the ratio of the amount of dry coal supplied to the A furnace 15 and the amount of dry coal supplied to the B furnace 16 is set to the ratio between the target amount of dry coal for the A furnace 15 and the target amount of dry coal for the B furnace 16. Can be the same. That is, it is possible to prevent the load ratio between the A furnace 15 and the B furnace 16 from collapsing. Further, since the correction unit 18D ₁ is formed by a simple arithmetic processing by subtraction (SUB), function generation (FG), and addition (ADD), the processing of the control device 18 is prevented from increasing significantly. 18D ₁ arithmetic processing can be realized.

(Embodiment 2)
The control device for the pressurized fluidized bed boiler according to this embodiment is a control device 18 shown in FIG. The unit including the control device 18 includes a fuel production system 11, a supply system 13, an A furnace 15, and a power generation device 17. In this embodiment, components that are the same as or the same as those in the first embodiment described above are denoted by the same reference numerals, and description thereof is omitted. In this embodiment, only the A furnace 15 is used as the boiler.

The fuel master 18D of the control device 18 according to this embodiment calculates the fuel amount (FRD) of the A furnace 15 from the total fuel amount (TFRD) by function generation (FG). The fuel master 18D, when L / C has been changed to correct the fuel amount of A furnace 15 (FRD) correction unit 18D _1.

  The pump control unit 18E uses an A1P pump command for controlling the pump (A1P) 13A of the supply system 13 and an A2P pump for controlling the pump (A2P) 13B based on the fuel amount (FRD) of the A furnace 15 calculated by the fuel master 18D. Commands are generated by function generation (FG), and these commands are sent to the supply system 13.

  According to this embodiment, even when a difference occurs between the actual output of the steam turbine generator of the power generator 17 and the output instruction (MWD) to the steam turbine generator, the amount of dry coal in the CWP is increased. Is controlled. As a result, the amount of air supplied is commensurate with the amount of dry coal in the CWP, so that the amount of air is prevented from becoming excessive, and the pressurized fluidized bed boiler can be operated stably. To do.

  As mentioned above, although each embodiment of this invention has been described in detail, the specific configuration is not limited to each embodiment, and even if there is a design change or the like without departing from the gist of this invention, It is included in this invention. For example, although the A furnace 15 and the B furnace 16 are used for supplying steam to the power generation device 17, the present invention is not particularly limited to this, and a boiler that generates steam necessary for heating of buildings and industrial fields is used. In contrast, the present invention is applicable.

1 is a configuration diagram of a unit including a control device for a pressurized fluidized bed boiler according to Embodiment 1. FIG. It is a block diagram which shows A furnace and B furnace. It is a figure which shows manufacture of CWP. It is a figure which shows the structure ratio of CWP. It is a figure which shows the structure of a control apparatus. It is a figure which shows the structure of a fuel master. It is a figure which shows an example of an input screen. It is a figure which shows an example of the screen showing a judgment result. 6 is a configuration diagram of a unit including a control device for a pressurized fluidized bed boiler according to Embodiment 2. FIG. It is a figure which shows the output raise in case the amount of coal of CWP is small. It is a figure which shows the several pressurized fluidized bed boiler in a unit. It is a figure which shows fuel amount control.

Explanation of symbols

DESCRIPTION OF SYMBOLS 11, 12 Fuel production system 13, 14 Supply system 15 A furnace 16 B furnace 17 Electric power generation apparatus 18 Control apparatus 18A Unit master 18B Boiler master 18C Water-fuel ratio master 18D Fuel master (control means)
18E Pump control unit

Claims (4)

When supplying CWP produced by a fuel production system capable of controlling the composition ratio of a plurality of coal, limestone and water to a pressurized fluidized bed boiler having a plurality of load distributions through a plurality of supply systems , respectively , A pressurized fluidized bed boiler that determines a total fuel amount of CWP based on a command value for setting an output of a generator that generates power with steam from a boiler and an output of the generator, and distributes the total fuel amount to the boiler In the control method of
Based on the amount of CWP coal supplied to the pressurized fluidized bed boiler and the amount of coal set for the boiler, the amount of CWP supplied to the boiler is calculated,
Comparing the calculated ratio of the coal amount of each CWP and the ratio of the set coal amount, and informing the necessity of adjustment of the water injection amount for the CWP supplied to each boiler,
A method for controlling a pressurized fluidized bed boiler, characterized in that: Determining the corresponding amount of CWP corresponding to the difference between the amount of CWP coal supplied to the pressurized fluidized bed boiler and the amount of coal set for the boiler;
Adding the corresponding amount to the amount of the total fuel allocated, and supplying CWP to the pressurized fluidized bed boiler, respectively.
The method of controlling a pressurized fluidized bed boiler according to claim 1 . Calculate the coal proportion based on the proportion of dry coal and limestone and the proportion of moisture in CWP,
The amount of coal is calculated from the amount of CWP supplied to the pressurized fluidized bed boiler and the coal ratio.
The method for controlling a pressurized fluidized bed boiler according to claim 1 or 2 . When supplying CWP produced by a fuel production system capable of controlling the composition ratio of a plurality of coal, limestone and water to a pressurized fluidized bed boiler having a plurality of load distributions through a plurality of supply systems , respectively , A pressurized fluidized bed boiler that determines a total fuel amount of CWP based on a command value for setting an output of a generator that generates power with steam from a boiler and an output of the generator, and distributes the total fuel amount to the boiler In the control device of
Based on the amount of CWP coal supplied to the pressurized fluidized bed boiler and the amount of coal set for the boiler, the amount of CWP supplied to the boiler is calculated, respectively. A control means for comparing the ratio of the amount of coal in the CWP and the ratio of the set amount of coal for each CWP and notifying the necessity of adjustment of the water injection amount for the CWP supplied to each boiler ,
A control apparatus for a pressurized fluidized bed boiler, comprising:

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